By Maya Auer and Louis Brady
The number of COVID-19 cases, deaths and hospitalizations by vaccination status will no longer be published on a weekly basis in Scotland, Public Health Scotland (PHS) has declared.
The body responsible for publishing COVID-19 data for Scotland revealed in their latest report that they will no longer publish weekly comparisons between COVID-19 rates within the vaccinated and unvaccinated populations.
In the report published on 16 February, the number of cases and hospitalization rates per 100,000 people were higher in the double-vaccinated and boosted populations than amongst unvaccinated people.
However, according to PHS, “uncertainty about the number of people in the unvaccinated population” makes comparisons of case rates “inappropriate.”
This uncertainty is due to the fact that the size of the unvaccinated population is determined by individuals’ GP records but it is difficult to determine if all these people are still in Scotland.
The data is “not robust” says Dr Diane Stockton, Consultant at PHS working on their weekly reports. The unvaccinated population in the data “is a mixture of people that will have chosen not to be vaccinated and then people that have left [the country],” Stockton told 9to5.
Students are an example of a group who move in and out of the country often and may be incorrectly counted as unvaccinated. “When students leave, the last thing on their mind is probably deregistering with their GP,” Stockton says. These students may still be counted in the unvaccinated figures.
The people in the vaccinated population, on the other hand, are known to have had recent contact with the health service due to vaccination.
PHS has made the decision to stop these weekly comparisons in light of “inappropriate use and misinterpretation of the data when taken in isolation without fully understanding the limitations.”
In a panel session on 17 February held by US Senator Ron Johnson in Washington D.C., high profile public anti-vaxx figures such as Dr Robert Malone as well as Paul E Alexander – epidemiologist and Canadian health researcher and ex-Trump administration official – both referred to the PHS data as being conclusive to the vaccine’s ineffectiveness. The American far-right news outlet Blaze Media further supported these claims.
However, due to its lack of robustness, the data “should not be used to assess how effective a vaccine is in preventing serious health outcomes,” says Stockton.
According to PHS, research also suggests that COVID testing and reporting behaviour varies between the vaccinated and unvaccinated, which may also make the comparative data inaccurate. Vaccinated people may be more likely to follow testing recommendations and reporting of results, which would make them “more likely to be identified as a case than unvaccinated people.”
The wrong underlying population also became more significant when the omicron variant reached Scotland, Stockton explained to 9to5. “The prevalence of omicron is much higher. If we’ve got a wrong underlying population, it didn’t matter as much for delta, it didn’t make that much difference. The problem was still there but because prevalence was a lot lower, the problem wasn’t exacerbated to the same extent as it is now.”
PHS will still publish comparative data, but not on a weekly basis, says Stockton. This will allow more time for further analysis and contextualisation of the figures.
Instead, PHS will place a larger focus on vaccine effectiveness studies and their results. “The vaccine effectiveness studies tend to compare double-vaccinated to boosted people to look at the additional benefit of the booster. They also use a methodology that only compares people who have reported test results. That gets around the issue of biases in people who are and aren’t reporting.”
Despite attempts to limit the misuse of PHS’ data, posts by some Twitter users suggest that the move could encourage further skepticism about COVID-19 figures, the vaccine, and public health authorities.
It remains to be seen whether the PHS’s decision will prevent anti-vaxxers from spreading misinformation, or whether it will fuel more mistrust in the effectiveness of the vaccine.